1. Field of the Invention
The present invention relates to an exhaust system hanger isolator which includes a steel bracket with first and second apertures formed therethrough at opposing ends, and having first and second rubber grommets received within the first and second apertures, respectively, for supporting exhaust system components on a vehicle in a manner to reduce noise and vibration.
2. Background Art
Exhaust pipes and mufflers in motor vehicles require a flexible support structure that will permit the exhaust system to expand and contract longitudinally along with changes in temperature. This flexible support structure must also insulate or isolate the exhaust system from the vehicle frame to prevent noise and vibration from being transmitted to the frame from the exhaust system.
It is desirable that such an exhaust system hanger isolator be inexpensive to manufacture and assemble while providing improved vibration isolation tunability and improved overall vibration isolation performance characteristics.
The present invention provides an exhaust system hanger isolator for supporting exhaust system components on a vehicle in a manner to reduce noise and vibration, wherein the isolator includes a steel bracket having first and second apertures formed therethrough at opposing ends of the bracket with first and second rubber grommets received within the first and second apertures, respectively, such that the rubber grommets are always in compression, rather than tension, thereby minimizing rubber material usage and enabling the use of very soft rubber grommet materials for improved performance. Preferably, the rubber grommets have chamfered ends to facilitate push-in insertion into the apertures. Also, the rubber grommets each include a central opening to receive a headed attachment rod which is pushed into the central opening for ease of assembly.
The bracket may be a single piece stamping which may include an integral heat shield formed as part of the single piece to shield the grommets from exhaust system heat, thereby further enabling the use of alternative grommet materials. The bracket is preferably a stamped galvanized steel, such as SAE 1008 or SAE 1018. Alternatively, the bracket could be a sintered metal or high temperature plastic.
The bracket design having apertures at opposing ends also enables the use of rubber grommets of different durometer at opposing ends of the bracket to enable tuning of noise and vibration isolation. Tuning may be further enhanced by providing cored holes in the grommets.
It is further contemplated that the exhaust system hanger isolator could have one, two or numerous rubber grommets, depending upon the particular design requirements. The rubber grommets may be injection or compression molded, and may comprise a EPDM or silicon rubber material. However, the term rubber grommets is used herein to refer to any elastic compressible material.
Accordingly, an object of the invention is to provide an improved exhaust system isolator having reduced manufacturing and assembly costs, tunable vibration isolation characteristics, and enhanced vibration isolation performance.
The above object and other objects, features and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings.